Motor



y 1944- F. G. FOL BERi'H ETAL 1 2,353,022

MOTOR Filed Jan. 16, 1942 4 Sheets-Sheet 1 INVENTORS FEEDER/CK aFOZBEE'TH & w zu/w M FDZBEEZ'H Maw ATTORNEYS July 4, 1944- F.G.VFOLBERTH T-Al.

MOTOR Filed Jan. 16; 1942 4 Sheets-Sheet 2 W/ll/AM N- rozznem A7'7'OENEYS July 4, 1944. F. GQFOLBIERTH ET AL 2,353,022

MOTOR Filed Jan. 16, 1942 4 Sheets-Sheet 4 w a \W W M w I my own M15 E04vro ma J Y B Patented July 4, 1944 T MOTOR 1 reed-arias Gf' Fdl'brth-and' William M." Folb'eith, t. .4 Clevelandjohio J 'al'iblitanpilJanuary 16, 1942; serial no; 426,942 (i olatin (o1; liar-15s) nYe b n els 150.5 fie dri sssiwer a a'ted motors and more particularlyatoyan irnero im tqr z .V6 mech nism eref peoially'adapted for eperatingwindshieldclean- ,l r O 'th fiin; ourgco pendi-ng llnited stateepatent; applis t nfierie e -z wz w fi da h 6 .9 and Serial NOl 412,lflZ file wseptebebfl;1941, we have described and claimed certain improvement iavfi i wpressur tu e -m v-Tl present applieation containecertaimsubj ectmattercommon =to said co- -pending; applications and certainimprovements not; disclosedin said applications, :and is-therefore racontinuation impart --9 ai p t n -.vt V ,7 V l; It is among theobjectswf our present-inven- ..tion to provide a compact, Jig-htweight,=-"effijcient and powerful fluid pressure actuated motor foroperating windshield cleaners; of; the osoillat-ing squeegee type, orother mechanisms v a a Other olojects of our invention-arethe provisionof a 'fl-uid' --pressureactuated unotor and; a -valve mechanism thereforwhich will alwaysin- H stantaneously start-uponapplicationof-fluid--under pressureg the+provision of-a-fiuidpressureac- -tuated; motor of the type described whichiscompletely free from. spring elements of; mankind; the provision of afluid pressure actuated-motor particularly: .adapted- -for operating-airplane .winjdshieldcleaners by means i of-oilorotherdiquid underpressure theprovision of a'fiuid pressure actuated motor; whichwill haveextremely low leakage if; for any-reason, the-driving -shaft of themotorisstopped or -stalledain-any"posi- 1 tion--- of its" cycle, such'asmight =possibly-oceurif 5 the -.squeegee blade of an.airplane-windshield 7 cleaner. should free zeta the windshield undericing conditions and,';the--provision= of arugged vmotor of the typedescribed which will operate forlong -periodsof time underall conditionsof service without-attention-or -adjustment,

The above and other "objects of our invention will appear from thefollowing description'oi'one embodiment thereof ,-referencebeinghadtothe accompanying drawings in which- Figure 1 is an endview of ourwindshield w, cleaner motor housed-in an-oil collecting casing, thecasingand a portion of'themotor shaft bearing being shown in crosssection. Figure 2 is a-lhorizontalcross; sectional view of themotor-andcasing shown in :Figure 1, taken substantially on line 2-2 ofFigure 1. V

Figure 3- is an end elevationa-lw'i-ewof the m0- tor-shown in Figure 19the-oil collecting-Cas being omitted. V p V 5 j o fthe-valve actuating.cylinders.

Figure 4 is a sideelevation of the. fiuid--pres- -sure supply sideof themotor,-taken on line 4-4 of Figure 3. a

Figure 5 is a side elevation-showingtheshaft side of the motonandtakemonlines-5 of-Figure 3. 1

"Figure '6 is 'a-vertical cross sectional view taken on'line 66 ofFigure 4.

- Figure 7 is avertical cross-sectional -v-iewtaken "on line 1 1of-Figure 4. V

Figure 8* is a fragmentary -'-ver-tical cross sectional view'taken onli-ne 8-8*o-f Figure 5.

Figure 9" is a longitudinal 'vertical' sectional view taken on line 9-9-of Figure 3.

Figure 10 is. a fragmentary cross sectional view of the valvemechanismof our-improved -motor, take'n On linel ii -=48- of Figure3;"and showingthe valve mechanism in one extreme position.

Fi'gure 11* is aview'similar t6'.|:"igll1 l()125111111- lustrating thevalve mechanism" ina'ri intermediateposition.

Figure 12 is a view"'similarto 'Fi'gureqO but shovvirigth'evalve'mecnanism'in the'oiapbsite' 'extreme position, I

""FigL' 13 is a'rragmntary cross'sectional View of the "valve'niechanismj "taken"ori "'l'ih I 3"-l 3 of Figure Gjahd showingthfvalv'e p'arts" in"w'hat "n'iayb'e described as a de'a'd"cnte1position.

Figure-14" is atr'ossseetionalnew si'rriila'r to Figureli'l, but showingthe valve parts in the extreme position corresponding'to'FigureflO.

Figure lti is a cross sectional'vi'ewsimilar to I Figurel3' but showingthe'valye'partslin the extreme position corresponding tolFigure 12,

Figure '16 is an enlarged cross sectional View taken on lineil6l6 t:Figure 13, ahdil1ustrating ceaampf the dead center preventing passages la Figure 17 isan enlarged cross sectional view taken on'lin |l"I1"of'Fig"ure 13, a'nd'showing certain other of the dead 'centerpreventing pas- Figure 18 is' an endelevation' oifthe main motor 4 blocko'r housing.

F'gurefillll is aside elevation of thernotor'block takenonline" 1 9-449of Figure 18. r

, jFig'ure 2Qis a lor' gitudinal sectional viewtaken "on line 2 0420ofFigure 'jIS. r ,7

Figure 21 is a cross sectional viewtaken on'line 2 !-Zl of.Figure 19. vc l Figure'Z'Z' is a fragmentary cross sectional" view l the connectionfrom the main v cylinder to. one

Fig. 23 is a detached side elevation of the outer tubular valve member.

Figure 24 is a cross sectional view taken on line 2424 of Figure 23.

Figure 25 is a cross sectional view taken on line 2525 of Figure 24.

Figure 26 is a detached side elevational view of the inner valve member.

Figure 27 is a cross sectional view taken on line 21-21 of Figure 26.

Figure 28 is a longitudinal sectional view taken on line 2828 of Figure27.

Figure 29 is a cross sectional view taken on line 2929 of Figure 26.

Figure 30 is a detached viewiof the main piston, portions of the endwalls being broken away to illustrate certain features of. itsconstruction,

Figure 31 is a detachedwi'ew of thedouble ended valve actuating plungeror piston, partly in section.

''Figure 32 is a side elevation of the o e member which connects thevalve actuating plunger shown inF ig ure 26.

' Figure '33 -isa' cros's' sectional view taken on line 33-33 of Figure32.

In th e' dra""ngs we "have illusftrated'our inventionas embodied in ahydraulic windshield shown in Figure 31 to theinner valve' member"cleaner motor. Referring particularly to Figures 1 and 2, the motor isreferred to generally by the "reference character" M'a'nd is' provided"with a shatt'be'a'ring portion which extends away from "the flange '2and through the side wall '3 "of the oil collecting c'a'sing C." wall 4may be considered to be a part of the structure :on which themotori'smounted'and, 'as'i's bestse'en in Figure 2,"screws 5 extend through thewall land spacermember 6 and are threaded into the flange 2.'Suitable'pa'cking material'sl"is"disposed"in a groove in the outer faceof flange 2 so that when the screws 5 are tightened the motor issupported in thecasing C and a fluid tight joint is established betweenthe flange -2 and'theside Wall 3 of the casing.

- -The motor shaft 8 extends-'beyond-the bearing I and may carry thesqueegee or-scraper arm 9 as illustrated in .Figures l and 2,'or may becon- In order to supply fluid under pressure tothe motor M, we provide avalve !3 having an inlet l4 connected to any suitable supply of fluidunder pressure. This valve may conveniently be of the typeillustrated inwhich turning the hand wheel 5 in one directionwill move the conical Vclosure member I6 away from its seat and turning it in the oppositedirection will move it toward the seat to close the valve. From thevalve l3 a pipe I! extends through the end wall of the casing C. Thevalve I3is'. preferably provided with packing 18 so that itmay betightened down against" the end wallof the casing C to preventleakage'atthi's'point. Pipe |1 connects the valve I 3 to the'fluid inlet passage31 'in the motor block;

Control ofthe starting,and"'stopping of the jmotor and'adjustmentofitsspeed is effected by theva'lve |3.f As will appe'ar'later, fluidwhich is exhausted from the motor M will be collected in the casing C'andwithdrawn through the pipe l2. As the casing forms a fluid-tightcover for the entire valve mechanism, a compact, clean, oil-tight unitis provided. It will be understood of course that the casing C shown inthe drawings is merely illustrative and that this casing may take otherforms, or other means may be provided for collecting the oil or otheroperating fluid from the motor M and conducting it away. Our motoritself includes a main block which 10 is best seen in Figures 3 to 5 and18 to 22. The

block may be referred to generally by the reference character B, and isformed with a main cylinder bore or chamber 20 extending longitu---dinally through its upper portion. Below the main; cylinder 20 andslightly to one side thereof is; the valve bore 2|, and adjacent thevalve bore 2| arethe two, small, spaced valve actuatingcylinders22-and"23; "As is perhaps best seen in Figure 5; these valveactuating cylinders are re]- 20 atively short, and do not extend thefull length *of the block B as do the main cylinder 20 and"the-valvebore 2-|-;-" l

Slots 24 and -25 --are spaced inwardly from-the ends of themain'cylinder 20, and a top slot 26 25 is cut through the upper wall of'theblock B 'into-the cylinder 20 to accommodate the gear 21 l which is"mounted on the drive shaft 8. The shaft bearing is secured to the topof the block *B by screws 28. The slots 24 and 25 are con- 30nected'to'thevalve actuating cylinders 23 and 22 respectively by meansof slanting holes 29 and 30. Recesses 3| in the end walls of the block B-complete the connection to the valve actuating cylinders 22 and 23 fromthe slots25 and 24.

In order to conduct fluid from-the valve cham- "ber 2| tothe maincylinder'20, spaced slots 32 -and--33-are formed-in-the walls of thevalve chamber 2|. -The slot 32 is connected to one end ofthe block B bya passage 34, and a similar 4.] passage 35 connects the slot 33'to theopposite end" of the block B. As is best seen in Figure 18, a recess 36in-the end of the block-'B-completes theconnectionfrom the valve chamber2| to the --m' ain"cylinder -20. A similar recess 36 is provided-0n theopposite end of the bloclr -B.

-'-The operating fluid -inlet 31 extends through "the wall of the valvechamber 2|, and is centrall-y disposed between the slots 32 and 33. For-reasons which will be fully explained later, we fiOialso provide smallholes 38 and 39 (see Figures 1-3-15) which "extend through the wall ofthe valve-chamber 2| into a recess 40, which is closed by the'screw plug4|; Figure 17 illustrates this arrangement in an enlarged view, and itwill be seen that oil may pass through hole 38 into the chamber 40, andthence through hole 39 '--back into the valve chamber. The location ofthe hole -40is clearly seen in Figures 18 and 19,

a boss 42 being formed on the block B. It will appearlaterthat the plug4| is provided solely 7O parting from our invention and the term pistonand cylinder are used herein in a broad sense. The piston Pcomprises'two cylindrical end portions 43 and 44, which are preferablyrecessed asseen 'at 45 in Figure 9. Notches 46 and 41 are 7:} cut in theends of the Walls of the'portions 43 rand-:44 -amd 'the:centerraportionr ofathe :pistonis loutawayz to form: as: has:rmembenvtfl havingarack i ntBGthJB-ethhfififi whichdengage' thevteethl. of theqrgear segment +21. "ZPhefllower? i part -59 of: :the 2 1131513011. is*formedeonwthe :sarne' diameterr'asi the (end: portions le ;E/I1'd44,:a-nd'-6mgaigS the wall; of ay-linden 26 thmirghouteitswlength. AI:--.:'Ph engagement ,ohthe rashioeeth wswiththe yygear 21,- -preventsirotat-ionofr-theipiston Ben t-he cylinder 26.1 Thusthm notcheseitiandxd'lnin(the :rends iofwpiston' P area-maintained; ineailignment vwith the. recesses. 3 Erin the end Walls-T1 :the :"block -B-. providingthesemotchesr E -anal fig'lzrentry of fluid r into the' recessed ends:of ether piston P Y is :permittecl; even: though ithe :zend fclosurepiates 5| sand 52 -are:in -:posi-tionnom theflelldsuofrothe wrblockB-'and thehpistorr P' is atc-anz extremeaend position as shown in Figure9. Suitable packing iifirimay be provided betweenrthei-renct mates 5 Iwand-52'-and-the bloclo:B-. 1

wt-lnl-the vaiwe chamber Zaizhretdisposedo-thetduter'utwbulahwarlveememberzgenerally indicated byz the V. deferencechar-eaten V and the: inner =valveimemwherfl/"netMechaniealconnections-in the iform of wa yoke Y Figure=3 aieiqironidedrbetweenathe inner rvaive member .Vri i ands theryaive' aetu'ating er plungerorepistonememheiz'lfz eRefeming-to: Figeflre =3kwit wil'lsiibeoseenflthatzitheemember P is :rpriwided.spaced:'cylindricalxendqportions -54 and. '55 and a flattened-connectinghate 56 eserews M51i'il igureimeeecturetthe web 585.101 the: yoke: Y a'tontheithanspohtion fifiru'f R and tthe end portions 59 and 60 of yokeYmreiafomiednwith U -shaped' slots5lg'as'seerr in Figure 33 These slots61" engage grooves 1 62 :a-n'd'v63 on the inner- ;v'alve memberV'"-"(Figure 26); anc'l' thusmeciprocation oftherplungerP will causecorrespond- 'mgvmovement ofirthe inner valve: member V. V .t Figure 5illustrates the asse-mbled relationship of the plunger P and yoke, Y;thefend portion '55 T bein-gdisposed inth'e smali-valveractuating cylin-,der23,4 and the portionfifl-beingdisposed in the 'small valve actuatedcyltnder Z2.--As the yoke Y --is secured to the-connecting bar56-bitheplunger ""P' ancl as th'eengagementof the slots (H- of the yokeYWith the-inner valvemember Vrdoes not :permit rotation of saidinnerv'alve V"; t-he angular relation o-f the inner valve -V in thevalve chamber 2| is maintained. Alsofthe projecting faces 32 (Figures -8and 33) or yoke Y have sliding engagement with thefaces 55and 66on theouter evalve member V 'andpreventrbtation of the outer valve- V relativeto the-inner -valve V and the valve chamber 2!. a

Referring now particularly to'Figures to 1'7 and 23 to 29, theconstruction and operation of our "improved self-starting,"non-stallalole valve mechanism willbe explained. Figure 10':illustrates the valve parts in=one extreme end position adapted tofeed-fiuid=uiiderz pressureto thev "left'hand end of the main 'cylinder--'as "seen in Figures 9 and' 20;"F1uidenters'thro'ugh'th inlet passage-31, "and is "directed into" the slot 33 by the spaced'flangs fil "and68' on'the outer valve V. These flanges '61'and 68have' a slidingfitirithe v'alve chamber '2l.' 'When'thGparts 'are'in' the position shownin Figur''lO,fluidtvillxmov' frbm slot 33 through the passage 35 intothe left hand end of the cylinder 2fi (as seen in FiguresQ and 20) andwill move the main piston P, to the right. As soon as piston P starts tomove, the slot'25 in. the. main cylinder will be closedoff and fluid Twill exhaust from the right hand endlof. cylinder space, in; thegzmainlvaive= :chamber betweem the flange fi l-randztheendrflang-e 69s Anopposite end =-flainge lila-on t he-iouter valve v-rconrespondstoflange: 679. r Fromvthisi spacel freespassagemo the 5 outside is.permitteduthrougmdischarge: opening -v e'lrl in the! block B -(seeFigure- 5'); A 'sim-ilarropenwing-:12 pemiitsnexhaust-from the*cyl'i-nderw 2'0 durringpepposite mnvement of-pthe piston P. i -Iuetbefiorethe piston? reaches-thearighthand 10- end1qt itslstrokwthe-slot24-in the=wall of main {"C YliIldEI-W 0 will' be :uncovered andfluid-under pressure will-be transmitted :through the passage ,and the:groove 31 "into: the valve actuating icylinde'i 2 3n lihis pressure'will move thefiplun-ger 1 5 member'1 and' with it, 'because' of-theconnecting "uyOkE .Y, the 'inner v'alve member V'. m'ove-. ment" i1)beR-tovthe right. in 'Fig'ur'e 10. During rrhtialwmovemnt-w of innerrvailve V";:==.the utenvalve' V-- will I not move; but-wheiiflth'e :hole2; '33 in' thel inneravalveoverlaps the f hole 14 in the outer-vad-ve,flinidwnder pressure- 'wiilpasstthroiigh ithe boreiil fi in thefltinervalveaand exert pressure on :theulefmtl'rand end of the inner va'lve-'assisting moving it xto'r'the' -ri'ght.:'= .It will b'e?seen!='that.Eringesmembers ilfia and z11 f(n'm rcylinder's rinto which the ends ofthe inhee'mzlvevzmay extend. -As'-soon' as the ena 1afomnnervaive'vtzleaves the firing- 16; as'rseenrin Fiure =11 -fltiid pressurewill bie 'a dmitted= against"theendrp'ortioni 10.?lo'f iouter 3 vailve'V. F'Du'ringi moverh'enti of'ninner waive: V isfrom the position inFigure '10 -'-t'o 'that shotvn in Figure llwfluid: tin? the r1ng '1Tim'ay i e-scape sthroughsth bores!!! .irmhrinner ilalve, ene P101880;and' tlie 'hdle'a'l in outerwalve Vwith aseamen:thernole waliensdurlngithershflting of :"tnewahze-"pa tis'iirom' left' thalite-During" movementor the outer' valve: o.th 'rignt"rrom the{positi'on shown =in iFi'gure 1'1 to that 'slmwn in Figure 1 2; fliiidmay eseape from tne hmrand m er'id of valve Wtnrou' h' the groove 82.Thee-11a fa.ce8i3 o'f "valv v prererably'reacnes"a1 hifient '{vfith'theouter end o'fi th grhove 82-just 13 or-to ehga'gemeneojfi the"end of'valve -V with' the -rin "member "VI-fi- B'y :thus clhsihg lofi"th freedischarge of fluidfrorn the ifi g h 't haind hd oF-the fifiain; vaaemsnsrny before; trflms' th ring 1112 a -easrnesing aetron is oetam whichstar s ufe aipearatuswew Q "at am nes-mm vibration li'olmd corraiispmnds' eliigiihple-ZLSB icorresponds t lible --18 l1 and-,sloti8fimorresponds mamas: irr the miier i ya lvlk'ai (1S0 52315.0, hbljerfiieornespeneawmiem, ehele'eafi to-(hole; 8ehtandhend rface989vtol'ntp ace20 throughthepassagevaaandslot. 32 into the 5761-83imtheagnteravalve-N.a; 1.4;; an 3.1

In order to explain the operation of our impi'oved means for preventingthe valve mechanism from remaining in a dead'center position, we referto Figures 13 to 17. Figure 13 illustrates the valve mechanism in whatwould be a dead center position were it not for the means "to bedescribed presently. When in the position shown in Figure 13 the flanges61 and on the valveV are aligned with and close the slots 32 and '33.Thus, if by any chance the valve mech- -anism should ever get into thisposition, fluid entering through the inlet 31 could not'reach 1 eitherend of the main cylinder 29 and the apparatus would not start. In orderto eliminate this possibility we provide a small centrally located hole90 (Figs. 16, 23) which extends into the inner bore 9! of the outervalve V. On the surface of the inner valve V, a groove, having ailongitudinal portion 92 and oppositely extending-end portions 93 and94, is formed. The hole 2 99 and the grooves 92, 93 and94 are so posi- Itioned, and are held so positioned by the yoke Y, i that the small hole90 .in the assembled device overliesthe outer end of the groove 93 (seeFigure 16) when the valve parts 92 are in the position shown in Figure13.

Thus if during-assembly of the device, or on account of vibration whenthe fluid supply is 'shut off, the valve parts should ever stop in theposition-shown in Figure 13, fluid may pass. through the hole 90 intothe groove 93 when the main control valve I3 is opened. From the groove93 fluid will pass through the groove 92 and groove 94 .and out throughthe hole 95 (Figure 17) which extends through the thickened portion 96of the valve V. This thickened portion 96 of valve! fits the inner-wallof the valve chamber 2|, and when the parts are in the centered positionshown in Figure 13, the hole 95 will align withthe small hole 38 in theblock B. Thus fluid will pass through the hole 38 into the chamber 49,back through the hole 39, and

=-through a hole 91, which also extends through the thickened portion 96of valve V into the inner bore 9| thereof. I

Another small hole 98 is longitudinally aligned with the end of the slot94 and extends through the wall of the inner valve V into the bore 15thereof. Again referring to Figure 13, it will be seen that in thecentered osition of the parts, the hole 98 is aligned with the hole 91and thus fluid will pass from hole 91 through hole 98 into the bore 15,and will be effective against the left hand end 18 of the inner valve Vto move it to the right out of its dead center position. As soon as thehole 13 inthe inner valve V aligns with the hole 14 in the outer valveV, pressure willbe applied to the left hand end 18 of the inner valve Vin the usual manner, and normal operation of the valve mechanism andpiston P will immediately commence.

By arranging the variousholesand passages just described in the mannershown in the drawings, the only time these holes will be effectivewill-be when the valve parts V'and V stop in the 'centered positionshown in Figure 13. As seen in Figure 14 when the valve parts are intheir extreme left hand position (corresponding to that shown in Figure10), the holes 95 and 91 are out of alignment with the holes 38 and 39,and thus no flow of fluid will take place through these small passages.So also, a similar disalignment of the holes 95 and 91 with holes 38 and39 occurs when the. parts are in their extreme right hand positions asshown-inlFigure 15. 1 At no time except when the parts are in thecentered position shown'in Figure 13 will a fluid conducting connectionbe established from the source of fluid pressure through these smallholes to the left hand end of the inner valve V, and thus at no timewill these small holes in any way interfere with the normal operation ofthe valve mechanism. The only time the small holes and grooves justdescribed come into action is when the valve mechanism is on what wouldotherwise be a dead center position. Thus these small holes and groovesmay be considered to be a safety feature which render our fluid pressuremotor self-starting at all times. ,This is particularly important inmotors for airplane windshield cleaners where failure of the motor tostart immediately when desired might be extremely senous.

In the mechanism described herein, we have provided a completelyself-starting fool-proof fluid pressure actuated motor, the valvemechanism of which is completely free of springs or other resilientmeans for assisting in the operation of the valve elements. If the shaft8 of the motor should be stalled in any manner at any part of itstravel, as might occur if a Windshield cleaner squeegee should freeze tothe glass, there will be no serious leakage of fluid through the motoreven though the operator neglects to turn off the main valve l3 becausethe valve mechanism and ports are so arranged that a direct connectionfrom fluid inlet to fluid exhaust is never established.

It will be understood that when the motor is enclosed in a casing asshown at C in Figures 1 and 2, the operating fluid, such as oil, whichis discharged through the exhaust openings H and 12, will be collectedin the casing C and withdrawn through the pipe l2. It will also beunderstood that the valve actuating plunger P,

which operates in the small cylinders 22 and 23,

does a minimum of work as it merely starts the inner valve member V onits movement and, after a relatively short movement by the plunger Y P,the full operating pressure is effective directly on the end valvemember V to complete its movement. Exhaust from the small cylinder 22 or23 which is not under pressure during a valve movement takes placethrough one or the other of the passages 29 or 39 and their terminalslots 25 and 24 into the interior of cylinder 29 adjacent the flattenedconnecting portion [8 of the piston P. Thus oil may pass out of the maincylinder 20 through exhaust holes 99 and Hill, which, as seen i inFigures 4 and 5, are centrally located on opposite sides of the block B.

Although the illustrated embodiment of our invention has been describedin considerable detail, reference is made to our copending United Statespatent applications referred to above for disclosure of somewhatmodified arrangements incorporating some of the features of the presentmotor and valve mechanism. Furthermore, we do not wish to be limited tothe specific embodiment of our invention herein shown and described, butclaim all forms thereof coming withv in the scope of the appendedclaims.

ing an inner valve member and an outer valve member in said valvechamber adapted when in one position to connect one end of said mainchamber to said fluid inlet aind the other end of said main chamber tosaid fluid outlet and when in another position to reverse saidconnections, said valve means having a dead center position in whichboth said inlet and said outlet are shut ofi'from said main chamber, andmeans, independent of said main chamber and operable only when saidvalve means is in said dead center position, for applying fluid underpressure to said inner valve member and thereby moving said valve meansout of said dead center position upon application of fluid underpressure through said fluid inlet to said valve chamber.

2. In a. fluid pressure actuated motor, a main chamber, a drive memberadapted to reciprocate in said main chamber, a valve chamber, fluidconducting connections from said valve chamber to said main chamber,valve means comprising an inner valve member and an'outer valve memberin said valve chamber, means for operating said valve means to controlthe flow of fluid through said connections, and means, eflective in anyposition of said drive member but only when said valve means is in aposition to shut ofi said main chamber from said valve chamber, forapplying fluid under pressure to one of said valve members and therebymoving said valve means out of said shut-ofl" position.

3. In a fluid pressure actuated motor, a main chamber, a drive memberadapted to reciprocate in said main chamber, a valve chamber, valvemeans comprising an inner valve member and an outer valve member in saidvalve chamber, a valve actuating cylinder, a valve actuating piston insaid valve actuating cylinder, mechanical operating connections betweensaid valve actuating piston and said valve means, fluid conductingconnections between said main chamber and said valve chamber, fluidconducting connections between said main chamber and said valveactuating cylinder, and means for conducting fluid under pressure tosaid valve actuating cylinder, said valve means having a dead centerposition in which the flow of fluid from said valve chamber issubstantially prevented, and means, independent of the position of saiddrive member and operable by fluid under pressure from said valvechamber only when said valve means is in dead center position, forconducting fluid under pressure to act on said inner valve member andthereby to move said valve means out of said dead center position andstart the motor in normal operation.

4. In a fluid pressure actuated motor, a main cylinder, a piston adaptedto reciprocate in said cylinder, a fluid inlet to the motor, fluidconducting means for conducting fluid to said cylinder from said inletand from said cylinder to exhaust, valve means for controlling the flowof fluid through said fluid conducting means to and from said cylinder,said valve means including inner and outer valve members, a valveactuating cylinder, a valve actuating piston in said valve actuatingcylinder, means for mechanically connecting said valve actuating pistonto said inner valve member, said inner and outer valve members having aposition in which fluid is substantially prevented from flowing eitherto or from said main cylinder, a plurality of fluid conducting passagesin said inner and outer valve members, said passages being positionedwhereby, when said inner and outer valve members are in said flowpreventing position, said passages conduct fluid under pressure fromsaid inlet to act on one end of said inner valve member to be effectiveto move said valve means out of said flow preventing position.

5. In a motor of the type described, a cylinder block member, a maincylinder in said block, a valve chamber in said block, a pair of spacedvalve actuating cylinders in said block, the longitudinal axes of saidmain cylinder, valve chamber and valve actuating cylinders beingsubstantially parallel, a double ended main piston having a reducedcentral portion and being adapted to reciprocate in said main cylinder,said block having fluid conducting passages extending from each end ofsaid main cylinder to spacedpoints in said valve chamber, said blockalso having fluid conducting passages extending from points spacedinwardly from each end of said main cylinder to the outer ends of saidvalve actuating cylinders, said block also having an opening through themain cylinder wall between said inwardly spaced points, a valveactuating plunger member having piston end portions joined by aconnecting bar, one of said piston end portions being disposed in one ofsaid valve actuating cylinders and the other of said piston end portionsbeing disposed in the other of said valve actuating cylinders, valvemeans disposed in said valve chamber, said valve chamber having spaceddischarge openings extending through the wall of said block, a yokemember secured to said connecting bar of said plunger member and havinglegs extending through said spaced openings and having drivingengagement with said valve means, a fluid inlet passage extending intosaid valve chamber, said valve means having a dead center position inwhich said fluid conducting passages from said main cylinder to saidvalve chamber are substantially completely closed, and means, effectiveonly when said valve means is in said dead center position, for movingsaid valve means out of dead center position upon application of fluidpressure through said inlet into said valve chamber.

6. A fluid pressure actuated motor of the reciprocating piston typehaving valve means for controlling the flow of fluid under pressure toeffect reciprocation of the piston, said valve means including an outervalve member having a bore extending longitudinally therethrough, aninner valve member having a sliding fit in said bore, said outer valvemember having spaced flanges adapted, whensaid outer valve is in oneposition, to shut off the flow of fluid to and from said piston, saidouter valve member having a hole extending into said bore between saidflanges and a second hole on the opposite side of one of said flangesfrom said first named hole and also extending into said bore, said holesbeing out of longitudinal alignment, said inner valve having a groove onthe surface thereof adapted, when said inner and outer valve members arein the center of their travel, to align with and connect said holes insaid outer valve member, and fluid conducting means, eflective only whensaid inner and outer valve members are in centered position, forconducting fluid from said second hole to one end of said inner valvemember whereby said fluid will move said inner valve member out ofcentered position.

FREDERICK G. FOLBERTH. WILLIAM M. FOLBERTH.

